Conventionally, a printing device having a casing in which a tape cassette is accommodated is known in the art. For example, in a printing device disclosed in Japanese Patent Application Publication No. 2014-194874, a casing includes a main body, an upper cover, and a cassette cover. The main body accommodates therein the tape cassette. The upper cover is positioned above the main body, and the cassette cover is positioned below the main body. A circuit board is provided in the main body at a position adjacent to the upper cover. A control circuit for controlling operations of the printing device is mounted on the circuit hoard.